Apparatus for folding web-shaped member

Abstract

An apparatus for folding a web of plastic film at predetermined locations and in a Z-shaped manner. The apparatus, by use of a mechanism for supplying the web material, has a pair of film feeding arms supplying the web material to the folded end portions in such a manner that the web material is pressed from front and rear surfaces different from each other, guided and supplied to the folded end portions, the web material is alternately guided around folded end holding members linearly movable at least from one side in the widthwise direction of the web material out of and into the respective folded end portions.

What is claimed is: 
     
       1. A folding device for an elongated continuous strip of plastic web material having laterally spaced elongate cuts formed therein at regular intervals in the longitudinal direction thereof, comprising: frame means;   a pair of spaced folded end receiving members mounted on said frame means;   means defining a pathway for said web material on said frame means;   reciprocal feed means on said frame means for feeding said continuous strip of plastic web material int zigzag manner so that web material sections are stacked one on top of the other between folded end portions thereon, said folded end portions thereon being oriented adjacent said folded end receiving members, said feed means including a pair of film feeding arms each having a proximal end and a forward end, said film feeding arms each being pivotally supported at said proximal end adjacent said folded end receiving members so that said forward ends of said film feeding arms are alternately movable to and from said folded end portions to orient said film in said zigzag manner, said film feeding arms being pivotal between an upright position inclined to the upper surface of said zigzag folded web material spacing said forward end from said folded end portions and a position parallel to the upper surface of said zigzag folded web material, each film feeding arm having intermediate said proximal end and said forward end a keep plate adapted to engage said upper surface of said web material folded in a zigzag manner, said keep plate having means defining holes therein that are alignable with said cuts when said keep plate engages said upper surface;   folded end holding members and drive means for supporting and driving said folded end holding members for movement toward and away from said folded end receiving members along at least one lateral edge of said pathway for said web material, said drive means causing, when said folded end holding members are moved away from said folded end receiving members, said folded end holding members to move out of a previously folded end of said web material to allow passage of said film feeding arms to said position parallel to said upper surface, said drive means causing, when said folded end holding members are moved toward said folded end receiving members, said folded end holding members to move into a location for guiding therearound said web material fed by said feed mechanism and effecting a tight clamping of said web material between said folded end holding means and said folded end receiving members; and   receiving means for receiving said folded web material thereon in said zigzag manner, said receiving means including at least one insert member received in said aligned cuts and holes in said keep plate when said film feeding arm is in said position parallel to said upper surface.   
     
     
       2. An apparatus according to claim 1, wherein said receiving means comprises a plurality of receiving surfaces. 
     
     
       3. An apparatus according to claim 2, wherein cutting means is provided for cutting off said web material between said plural receiving surfaces. 
     
     
       4. A folding device as set forth in claim 3, wherein said receiving means includes a tying means for tying said web material folded on said receiving surface by use of a tying member insertable through said insert members. 
     
     
       5. A folding device as set forth in claim 4, wherein a pair of said receiving surfaces are provided, said receiving surfaces being movable in a horizontal direction, and wherein a cutting device is provided at an intermediate position between said receiving surfaces. 
     
     
       6. A folding device as set forth in claim 5, wherein: perforated lines are formed at an intermediate portion between said folded end portions in the widthwise direction of said web material;   said cuts are each larger in width than a perforation on said perforated lines; and   said insert members are erected on said receiving surfaces and are inserted through said cuts.   
     
     
       7. A folding device as set forth in claim 5, wherein said tying means comprises a bending member for bending the forward end portions of said tying members inserted through said insert members. 
     
     
       8. A folding device for an elongated continuous strip of plastic web material having laterally spaced elongate cuts formed therein at regular intervals in the longitudinal direction thereof, comprising: frame means;   a pair of spaced folded end receiving members mounted on said frame means;   means defining a pathway for said web material on said frame means;   reciprocal feed means on said frame means for feeding said continuous strip of plastic web material in a zigzag manner so that web material sections are stacked one on top of the other between folded end portions thereon, said folded end portions thereon being oriented adjacent said folded end receiving members, said feed means including a pair of film feeding arms each having a proximal end and a forward end, said film feeding arms each being pivotally supported at said proximal end adjacent said folded end receiving members so that said forward ends of said film feeding arms are alternately movable to sand from said folded end portions to orient said film in said zigzag manner, said film feeding arms being pivotal between an upright position inclined to the upper surface of said zigzag folded web material spacing said forward end from said folded end portions and a position parallel to the upper surface of said zigzag folded web material, each film feeding arm having intermediate said proximal end and said forward end a keep plate adapted to engage said upper surface of said web material folded in said zigzag manner, said keep plate having means defining holes therein that are alignable with said cuts when said keep plate engages said upper surface; and   a plurality of receiving surfaces for receiving thereon said zigzag folded web material, said receiving surfaces each having at least a pair of holes therethrough;   two rod-like insert members on each of said receiving surfaces received in said cuts in said web material in response to said keep plate pressing down on said upper surface when said film feeding arm is in said position parallel to said upper surface; and   means for tying said web material in a predetermined quantity, including tying members inserted into said cuts in said web material through said insert members and a bend member for bending one end of a said tying member inserted into a superposed arrangement of said cuts.